Not applicable
Not applicable
The practice of removal of debris from oil and gas wells is well documented and there are many examples of prior art which include scrapers and brushes to mechanically clean the interior casing of the well. Likewise there are examples of tools designed to remove the debris from the wellbore after it has been scraped and/or brushed. These include junk subs, debris filters, circulation tools, magnets and other similar tools. There also exists several examples of magnetic downhole tools.
There are also examples of tools designed to jet the Blow Out Preventers (BOPs), Wellhead and other cavities found in the wellbore. There also exists in prior art tools which combine the action of BOP jetting and magnetic attraction.
The present invention relates to wells for producing gas and oil and, more particularly, to wellbore cleaning tools, and more particularly, to magnetic wellbore cleaning tools which collect ferromagnetic materials suspended in wellbore fluid.
When drilling an oil or gas well, or when refurbishing an existing well, normal operations may result in various types of metal debris being introduced into the well. Downhole milling produces cuttings which often are not completely removed by circulation. Other metallic objects may drop into and collect near the bottom of the well, or on intermediate plugs placed within the well.
Various drilling and cleaning operations in the oil and gas industry create debris that becomes trapped in a wellbore, including ferromagnetic debris. Generally, fluids are circulated in such a wellbore to washout debris before completion of the well. Several tools have been developed for the removal of ferromagnetic debris from a wellbore. There is a continuing need for a more effective magnetic wellbore cleaning tool.
In one embodiment the magnetic wellbore cleaning tool removes ferromagnetic debris from a wellbore wherein the tool body can be attached to a work string and lowered into a wellbore.
In one embodiment upper and a lower centralizers can be placed on the tool body.
In one embodiment the tool body can have a plurality of longitudinal ridges, each of the plurality of ridges having openings or recesses for holding magnets, wherein the magnets are circumferentially spaced about the body and are aligned in a parallel direction with respect to the longitudinal axis of the tool body.
In one embodiment one or more magnets can be held in place in the opening or recess by a retaining plate. In one embodiment the retaining plate can be slid into a locking position using a slot in a longitudinal ridge. In one embodiment the retaining plate can have one or more openings for exposing a portion of one or more magnets being retained in the opening or recess.
In one embodiment the retainer plate can have a quick lock/quick unlock system wherein in the locked stated the plate is held in place in the slot, and in the unlocked state the plate can slide out of the slot. In one embodiment the quick lock/quick unlock system can include a biased locking connector such as a grub screw.
In one embodiment the plurality of longitudinal ridges can be detachably connected to the tool body. In one embodiment the plurality of ridges can slidably connect to the tool body.
In one embodiment the tool body can include an longitudinal bore which is fluidly connected to the drill string bore, and include a plurality of jetting ports which are fluidly connected to the longitudinal bore of the tool body.
In one embodiment each longitudinal ridge can include at least one jetting nozzle, and in other embodiments can include a plurality of jetting nozzles.
In one embodiment the plurality of ridges when attached to the tool body can form an annular area, wherein the annular area is fluidly connected to the longitudinal bore of the tool body and at least one of the plurality of jetting nozzles.
While certain novel features of this invention shown and described below are pointed out in the annexed claims, the invention is not intended to be limited to the details specified, since a person of ordinary skill in the relevant art will understand that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation may be made without departing in any way from the spirit of the present invention. No feature of the invention is critical or essential unless it is expressly stated as being “critical” or “essential.”
The apparatus of the present invention solves the problems confronted in the art in a simple and straightforward manner. One embodiment provides an improved wellbore cleaning method and apparatus whereby wellbore cleanup tools performing the functions of a magnet cleanup tool.
One embodiment relates to a method of attachment of a magnet to a downhole magnetic tool, where the tool will be used for wellbore cleanup.
One embodiment includes a downhole magnet tool where the magnets are attached to an integral tool body.
One embodiment includes a downhole magnet tool where the magnets are attached to a removable sleeve which is mounted to an integral tool body
One embodiment includes an integral tool body or sleeve on a tool body, the body having a interior longitudinal bore with fluidly connected radial ports passing through the magnetic section which ports can be used for jetting.
In one embodiment is provided a method of attaching commercially available magnetic strips to a customized tool body in a low cost and reliable manner whereby the magnets are securely attached to the tool, whereby the primary attachment method is backed up by one or more supplementary attachment methods to prevent accidental removal downhole.
In one embodiment a plurality of magnets can be attached to a tool body wherein the tool body is included as part of a drill string and magnets are attached to milled ribs running longitudinally along the tool body. In one embodiment the outside diameter of the plurality of ribs can be slightly less than the wellbore internal diameter, which centralizes the tool and maximized exposure of the magnetic surface of the magnets. In various embodiments the outside diameter of the ribs can be 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, and/or 85 percent of the internal diameter of the wellbore. In various embodiments the outside diameter of the ribs can be a range between any two of the above specified percentages.
In one embodiment, the magnets can be attached to an externally mounted ribbed sleeve. In this embodiment the ribbed sleeve can also be used as a jetting sleeve which includes a plurality of jetting ports to selectively jet blow out preventers (“BOPs), wellheads, and/or risers as desired by the user. The BOP's, etc. are of larger internal diameter than the wellbore and the jetting sleeve can be sized to suit these larger diameters, typically 16” or 11″ outer diameters.
In various embodiments, the plurality of magnets can be mounted on the tool in one of two fashions: (1) attached to longitudinal ribs, or (2) mounted between ribs facing radially outward from the longitudinal center of the tool body.
Various embodiments may include jetting ports drilled radially through one or more of the ribs, wherein the jetting ports can be used to clean the BOP, riser, and/or wellhead, and the magnets can be used to catch debris dislodged during the cleaning process, such as the jetting process. This is of additional benefit inside a riser which has a large internal diameter (e.g., 19-22″) and where low circulation rates make circulation of debris to surface problematic, if not impossible.
One embodiment includes attaching the magnets by milling pockets into longitudinal ribs or milling tangential pockets into the external circumference between the longitudinal ribs. In one embodiment the magnets are inserted into elongated longitudinal pockets (wherein the magnets are rectangular in form), a magnet spacer can be used to hold the magnets in place and offset from other magnets and from the ferrous body or sleeve. In one embodiment a magnet retainer can next be inserted into a recessed slot which retains the magnets by overlapping a small portion around the edges of the magnet. The magnet retainer is prevented from being accidentally removed by including internally installed grub screws and springs which are backed out into mating internal slots on the magnet retainer. In one embodiment is provided bissell pins as a final method of security for securing the magnet retainer.
In one embodiment is provided a tool which can be suspended in a well to retrieve ferrous metal debris from the well. In one embodiment the tool can include an elongated tool body having a plurality of circumferentially arranged magnets in openings, pockets, or recesses. A plurality of magnets may be positioned in each opening, pocket, or recess, and one or more magnet retaining plates can be used for detachably securing the magnets in place.
In one embodiment the tool body can include a central bore for pumping fluid through the tool body and/or through one or more jetting nozzles located on the tool body, and the upper end of the tool body is configured for attaching to a tubular extending into the surface.
In one embodiment of the method, a tool body can be provided with a plurality of openings, pockets, or recessed slots as discussed above, and magnets are positioned within each slot and are held in place by one or more retaining plates which are detachably secured to the tool body. The tool with magnets may then be positioned in the well for collecting and subsequently retrieving metal debris.
In one embodiment the magnets can be held within the tool body, yet removed from the tool body during operations at an oil and gas drilling rig. In one embodiment the tool may be used and cleaned and repaired in a field operation at the drilling rig.
In one embodiment each of the plurality of magnets can be completely recessed in the tool body.
Detailed descriptions of one or more preferred embodiments are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in any appropriate system, structure or manner.
For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:
Unitary Body with Magnetized Ridges
Generally, magnetic tool 10 includes an elongated tool body 100 having a plurality of magnetized longitudinal ridges 200. Between pairs of magnetized ridges can be collection areas for ferrous debris.
Tool body 100 can include upper box end 110, lower pin end 120, central bore 130 running through tool body 100, and longitudinal axis 134. In one embodiment, upper end 110 can be configured for receiving a tubular for suspending the tool body in the well, and for passing fluid through central bore 130 in tool body 100. In other embodiments, tool 10 may be configured for connection to a wireline, or to another type of tubular for suspending the tool in the well.
In one embodiment tool body 100 can include ridges five magnetized longitudinal ridges (500, 900, 1000, 1400, and 1420) which are symmetrically spaced radially about longitudinal axis 134. In one embodiment the five longitudinal ridges can be equally radially spaced about 72 degrees apart. In various embodiments the individual ridges can be constructed substantially similar to each other. In varying embodiments a varying numbers of longitudinal ridges can be used including 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, and 15. In different embodiments a range of ridges can be used which range varies between any two of the above specified number of ridges.
In various embodiments each of the magnetized longitudinal ridges can be constructed in a substantially similar manner though the use of inserting a plurality of magnets in openings of the ridges. Representative magnetized longitudinal ridge 500 will be explained in detail below, however, it is to be understood that longitudinal ridges 900, 1000, 1400, and 1420 are substantially similar to ridge 500 and will not be separately described.
First ridge 500 can comprise first end 510 and second end 520, and include first side 530 and second side 540. First ridge can have first opening 600 and second opening 650 which openings can each house or contain a plurality of magnets.
First opening 600 can have first side 610 and second side 620 with sides walls 630. Adjacent second side 620 can be reduced area 640.
Second opening 650 can have first side 660 and second side 670 with sides walls 680. Adjacent second side 670 can be reduced area 690.
First ridge 500 can include slot 550 for first ridge which is located on the first sides 610, 660 of first 600 and second 650 openings. Slot 550 can accept one or more retaining plates 800,800′ to retain in place magnets housed or stored in first 600 and second 650 openings.
Spacer 700 can comprise first end 710 and second end 720, and have first side 730 and second side 740. Spacer can include middle portion 750 with first 760, second 762, third 764, and fourth 766 recessed areas. Spacer can be used to retain and space apart a plurality of magnets. First 760, second 762, third 764, and fourth 766 recessed areas can respectively space apart first 761, second 763, third 765, and fourth 767 magnets.
A plurality of magnets can be included in each opening 600 and 650. Multiple magnets can be used in each opening in each ridge and the multiple magnets can be spaced apart and positioned using a spacer. The pole orientation of such multiple magnets can be controlled by the user depending on the manner of inserting such magnets in the spacer. In one embodiment poles like poles are faced toward one another. In another embodiment, unlike poles are faced toward one another.
Spacer 700 with spaced apart first 761, second 763, third 765, and fourth 767 magnets can be inserted into first opening 600 of ridge 500. Spacer 700′ with spaced apart first 761′, second 763′, third 765′, and fourth 767′ magnets can be inserted into second opening 650 of ridge 500. Spacer 700 can be comprised of a non-ferrous magnet material. First 760, second 762, third 764, and fourth 766 recessed areas can respectively space apart first 761, second 763, third 765, and fourth 767 magnets. Additionally, first 761, second 763, third 765, and fourth 767 magnets can be of differing strengths and/or polarity (i.e., north and south pole configurations).
After being placed in an opening, the plurality of magnets can be held in place in first opening using a retaining plate 8000 on one side of ridge 500 (e.g., first side 530), and a reduced area 640 of first opening 600 on second side 540. In this manner both first side 530 and second side 540 have magnets and a single retaining place can be used to retain in place the magnets for both sides 530 and 540.
Retainer plate 800, on first end 810, can include locking openings 860 and 864 for a grub screw and bissel pin. On second end 820 it can include locking openings 868 and 872 for a grub screw and bissel pin.
Making up of the magnets in one magnetic ridge 500 will be described below. Making up the remainder of the magnetic ridges (900, 1000, 1400, and 1420) for magnet tool 10 can be performed in a substantially similar manner and will not be described separately. Spacer 700 with spaced apart first 761, second 763, third 765, and fourth 767 magnets (first 760, second 762, third 764, and fourth 766 recessed areas can respectively space apart first 761, second 763, third 765, and fourth 767 magnets) can be inserted into first opening 600 of ridge 500. Spacer 700′ with spaced apart first 761′, second 763′, third 765′, and fourth 767′ magnets (first 760′, second 762′, third 764′, and fourth 766′ recessed areas can respectively space apart first 761′, second 763′, third 765′, and fourth 767′ magnets) can be inserted into second opening 650 of ridge 500. Retaining plate 700′ can be slid into slot 550 until above second opening 650 of ridge 500. Retaining plate 700 can be slid into slot 550 until above first opening 650 of ridge 500. Now first 761′, second 763′, third 765′, and fourth 767′ magnets are retained in opening 650 between reduced area 690 and retaining plate 800′. Additionally, first 761, second 763, third 765, and fourth 767 magnets are retained in opening 600 between reduced area 640 and retaining plate 800. Grub screws 582, 590 are respectively threadably backed out of openings 580,588 to interlock with openings 820′,860′ of retaining plate 800′—locking in place retaining plate 800′ over opening 650. Grub screws 562, 578 are respectively threadably backed out of openings 560,568 to interlock with openings 820,860 of retaining plate 800 locking in place retaining plate 800 over opening 600. Additionally, bissel pins 586,594 are used to also lock in place retaining plate 800′ (inserted into openings 584,592). Bissel pins 586,594 are used to also lock in place retaining plate 800′ (inserted into openings 584,592). Bissel pins 566,574 are used to also lock in place retaining plate 800 (inserted into openings 564,572).
After use to remove and/or replace magnets the opposite procedure to that described in the immediately proceeding paragraph can be used where the bissel pins are pulled out, and the grub screws are respectively threaded into their respective grub screw opening, and the retaining plates slid out of slot 550 so that the magnets and spacers can be removed from openings 650 and 600.
Magnet tool 10 retrieves ferrous metal debris from a well, and includes an elongate tool body 100 having a plurality of circumferentially arranged ribs 500, 900, 1000, 1400, and 1420 each for holding a plurality of magnets.
After usage, magnet tool 10 can be cleaned relatively easily.
According to the method, the tool is provided with the ribs and the magnets, and is suspended in a well to retrieve various metal debris.
Inserting Magnets in Ridges for Tool Body 100.
In removing the magnets from the openings in the ridges, a reverse operation of what is discussed above can be performed by removing bissel pins, screwing back in the locking grub screws, and sliding out the retaining plates from their respective holding slots. After the retaining plates are removed, the spacers with spaced apart plurality of magnets can be removed from their respective openings.
Detachable Sleeve with Magnetized Ridges and Jetting Ports
Generally, magnet tool 10′ comprises tool mandrel 2000 with detachably connectable magnetized sleeve 2500. Sleeve 2500 can include a plurality of magnetized longitudinal ridges 200 (e.g., ridges 500, 900, 1000, 1400, and 1420) wherein the magnetized ridges have openings or pockets on either side of the ridges for magnets. Each of the plurality of magnetized ridges can include a plurality of magnets for collection of ferrous debris. Between pairs of magnetized ridges can be collection areas for ferrous debris. In this embodiment, detachable sleeve 2500 is shown having a plurality of jetting ports 2700 in each of its plurality of magnetized ridges
The detachably connectable magnetized sleeve 2500 provides flexibility with magnet tool 10′. In different embodiments one can use the same mandrel 2000 and have several different types of sleeves (2500, 2500′, 2500″) detachably connectable to mandrel 2000 (either at different times or connected simultaneously), or no sleeve at all which reduces inventory and allows better utilization of assets.
With different sleeves, for the same mandrel 2000, different set up configurations can be used which possibly change one or more of the following features/functions/properties:
(a) number of magnetized ridges;
(b) size of the magnetized ridges;
(c) configuration of the magnetized ridges including but not limited to height and width of the ridges, orientation of the ridges, length of the ridges and spacing of the ridges;
(d) number of jetting ports;
(e) configuration of the jetting ports; and
(f) number of magnets and/or size of magnets.
In one embodiment, it is possible to reconfigure magnet tool 10′ at the wellsite to suit the application if so desired. In one embodiment magnet tool 10′ can be shipped with at least two sleeves 2500 and 2500′ with only one of the sleeves detachably connected to mandrel 2000. During use at the well site, after being used in the well the first connected sleeve (e.g., 2500) can be removed from mandrel and second sleeve (e.g., 2500′) detachably connected to mandrel 2000 and then lowered downhole for wellbore operations. In one embodiment sleeve 2500 and 2500′ are substantially similar to each other. In another embodiment sleeve 2500 and 2500′ of differing configurations based on one or more of the above specified features/functions/properties. In one embodiment the switching between sleeve 2500 and 2500′ is performed before magnet tool 10′ is lowered downhole for wellbore operations.
In another embodiment, differing mandrels (e.g., 2000 and 2000′) can be used with sleeve 2500. For example, a mandrel 2000′ with brush and/or scraper elements can be attached to sleeve 2500 and lowered downhole.
With the above interchangeable embodiments a single magnet tool 10′ can be shipped to a user and such tool configured at the wellsite according the user's needs by selectively choosing either from a plurality of sleeves and/or a plurality of mandrels to be detachably connected together and perform wellbore cleaning operations downhole.
Maintenance/Inspection
Downhole tool bodies must be tested periodically using non-destructive magnetic particle inspection. If the sleeve is not part of the body it does not need to be inspected, saving costs
Mandrel 2000 can include upper box end 2010, lower pin end 2020, central bore 2030 running through mandrel 2000, and longitudinal axis 2034. In one embodiment, upper end 2010 can be configured for receiving a tubular for suspending tool body in the well, and for passing fluid through central bore 2030 in mandrel 2000. In other embodiments, tool 10′ may be configured for connection to a wireline, or to another type of tubular for suspending the tool in the well.
Detachable sleeve 2500 can include first end 2510, second end 2520, longitudinal bore 2530, and a plurality of magnetized ridges. In one embodiment detachable sleeve 2500 can include ridges five magnetized longitudinal ridges (500, 900, 1000, 1400, and 1420) which are symmetrically spaced radially about longitudinal axis 2034. In one embodiment the five longitudinal ridges can be equally radially spaced about 72 degrees apart. In various embodiments the individual ridges can be constructed substantially similar to each other. In varying embodiments a varying numbers of longitudinal ridges can be used including 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, and 15. In different embodiments a range of ridges can be used which range varies between any two of the above specified number of ridges.
In
In one embodiment the a plurality of nozzle output jetting lines 2900 are provided which are fluidly connected to central bore 130 allowing fluid from the string to both pass through the tool body 100 and exit the end of the drill string, and also through the output lines 2900 to facilitate washing of the well to free debris along with an upward flow of debris and increase the amount of collection of debris on the magnets. Because each ridge (e.g., ridge 500, 900, 1000, 1400, and 1420) can be constructed substantially similar to each other, only one ridge will be discussed below (with it being understood that the remaining ridges are substantially similar and need not be described again).
In one embodiment each longitudinal ridge (e.g., ridge 500) can include a plurality of jetting lines 2900. For example In different embodiments the number of jetting lines (e.g., 2910, 2920, 2930, and 2940) in a ridge (e.g., ridge 500) can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, and 15 (with four shown in the figures for simplicity). In various embodiments the number of jetting lines in a ridge can be within a range between any two of the above specified number of jetting lines.
In various embodiments each jetting line in a ridge of the plurality of jetting lines can include a jetting nozzle. In various embodiments nozzles (e.g., 2916, 2926, 2936, and 2946) can be attached to each jetting line (e.g., 2910, 2920, 2930, and 2940), and can be substantially the same size. In various embodiments the nozzles (e.g., 2916, 2926, 2936, and 2946) can be of different sizes. In various embodiments each ridge (e.g., 500, 900, 1400, and 1420) can include a plurality of jetting lines (e.g., 2910, 2920, 2930, and 2940) and the user is provided with the option of selectively closing or shutting off one or more of the jetting lines in such ridge.
In various embodiments the plurality of exits from the plurality of jetting lines in a ridge can create jets of differing angles when compared to the longitudinal centerline 2034 of magnet tool 10′. In various embodiments (e.g., as shown in
In various embodiments a plurality of a ridge can be substantially perpendicular to the longitudinal center line 2034 (e.g., lines 2920′ and 2930′), and a plurality of the jets of the same ridge can be other than substantially perpendicular to the longitudinal center line 2034 (e.g., lines 2910′ and 2940′) and at least three of the jets of the same ridge are not parallel to each other (e.g., line 2910′ being not parallel with line 2940; line 2910′ being not parallel with line 2920′ or line 2930; and line 2940′ being not parallel with line 2920′ or line 2930′). In various embodiments the non-parallel lines can be angled from the longitudinal centerline 2034 by 15, 20, 25, 30, 40, 45, 50, 55, 60, 65, 70, and 75 degrees. In various embodiments the non-perpendicular lines can be within a range between any two of the above specified degree measurements.
In various embodiments the plurality of jets for a particular longitudinal ridge can exit from the ride at a point which is between the two sets of magnets on either face of the ridge. For example, in ridge 500 plurality of jets 2910, 2920, 2930, and 2940 exit between sides 510 and 520 of ridge 500. In various embodiments the plurality of jets 2910, 2920, 2930, and 2940 exit between spaced apart on either side of the ridge (e.g., jets 2910, 2920, 2930, and 2940 exit between magnets in opening 600 on first side 530 and opening 650 on second side 600 of ridge 500).
Jetting and Magnetized Pickup Operations
Tool assembly 10′ is supported by drill pipe 410 and located inside of blow out preventer 380. Tool assembly is shown as having jetting ports 2900 which are being used to jet or spray out fluid in the area of blow out preventer 380. Arrows 2910 schematically indicate streams of jetted out fluid. Such jet streams create an area of mixing 2920 wherein debris can be cleaned from the walls and movement of particles can be cause. Such movement of particles allow magnetic particles which come within the magnetic field lines created by the plurality of magnets in the ridges to be pulled towards and captured by the magnets creating the magnetic fields.
Having jet nozzles 2900 between sets of magnets on the plurality of ridges assist is believed to assist in the collection of debris when compared to no jetting or jetting above and below the magnets. Jet nozzle placement is believe to assist with ferrous metal attraction as the jet stream from a jet nozzle will induce movement of fluid from behind the stream and create eddy currents which tend to cause debris to flow along magnetic field lines and end up captured on one of the faces of the plurality of magnets thereby exposing more suspended debris to the magnetic fields.
Different directions of jetting nozzles can also assist in dislodging debris from the well bore such as from blow out preventers. Having different angles of jetting nozzles assists in the dislodgment process as debris is jetted from different angles.
Detachable Sleeve with Magnetized Valleys and Jetting Ports in Ridges
Although specific embodiments of the invention have been described herein in some detail, this has been done solely for the purposes of explaining the various aspects of the invention, and is not intended to limit the scope of the invention as defined in the claims which follow. Those skilled in the art will understand that the embodiment shown and described is exemplary, and various other substitutions, alternations and modifications, including but not limited to those design alternatives specifically discussed herein, may be made in the practice of the invention without departing from its scope.
The following is a list of Reference Numerals used in the present invention:
It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above. Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention set forth in the appended claims. The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.
This is a continuation of U.S. patent application Ser. No. 13/710,653, filed Dec. 11, 2012 (issued as U.S. Pat. No. 9,121,242 on Sep. 1, 2015), which claims benefit of U.S. Provisional Patent Application Ser. No. 61/712,059, filed Oct. 10, 2012, each of which are incorporated herein by reference and to which priority is hereby claimed.
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20160097261 A1 | Apr 2016 | US |
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61712059 | Oct 2012 | US |
Number | Date | Country | |
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Parent | 13710653 | Dec 2012 | US |
Child | 14842423 | US |